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At least 1,531 records · Page 85

Frequency switch keyed oscillator

Oscillator changes resonant frequency of the LC tank circuit by shunting one of a pair of parallel capacitors. Technique reduces amount of hardware required to interrogate and control remote systems.

Katchis, L.↗

Generating social impact scenarios, a key step in making technology assessment studies

The social impact scenario, a method used to trace the effects of new technological applications, is discussed. The research seeks to anticipate the secondary social impacts that arise from: (1) government or private programs that cope with major social problems like poverty, environmental pollution, or public safety; and (2) a concerted national effort to achieve a widely supported specific goal like landing a man on the moon or finding a cure for cancer.

Jones, M. V.↗

Phase shift keyed, pulse code modulated signal synchronizer

Signal is demodulated and synchronized by three loop circuits: ''Q'' loop uses quadrature signal to stabilize frequency; ''B'' loop acts on baseboard signal to stabilize phase; and decoding ''I'' loop acts on in-phase signal. Synchronizer may be used to eliminate false-lock.

Kobayashi, H. S.↗

Apollo management: A key to the solution of the social-economical dilemma - The transferability of space-travel managerial techniques to the civil sector

An analysis has been conducted to find out whether the management techniques developed in connection with the Apollo project could be used for dealing with such urgent problems of modern society as the crisis of the cities, the increasing environmental pollution, and the steadily growing traffic. Basic concepts and definitions of program and system management are discussed together with details regarding the employment of these concepts in connection with the solution of the problems of the Apollo program. Principles and significance of a systems approach are considered, giving attention to planning, system analysis, system integration, and project management. An application of the methods of project management to the problems of the civil sector is possible if the special characteristics of each particular case are taken into account.

Puttkamer, J. V.↗

Polarization - A key to an airborne optical system for the detection of oil on water.

Skylight polarization, which varies with the position of the sun in the sky, influences the contrast of oil on water. Good contrast is most consistently obtained by viewing in azimuth directions toward or away from the sun. Contrast is enhanced by imaging selected polarization components and by taking the difference between orthogonal polarization components.

Millard, J. P.↗

The space station: Key to living in space

Design and scientific equipment for the Manned Orbiting Laboratory and Skylab are elaborated. Multideck designs accommodate both zero gravity and artificial gravity conditions as well as a core module potentially useful as a planetary mission module for a 12-man crew. Artificial gravity approaches consider assembly rotation and differential spin rates for the various decks. Counterrotation systems are projected to go from a station to a 50-man space base concept.

Lord, D. R.↗

Bibliography on aircraft fire hazards and safety. Volume 1: Hazards. Part 1: Key numbers 1 to 817

Ignition temperatures of n-hexane, n-octane, n-decane, JP-6 jet fuel, and aircraft engine oil MIL-7-7808 (0-60-18) were determined in air using heated Pyrex cylinders and Nichrome wires, rods, or tubes. Ignition temperature varied little with fuel-air ratio, but increased as the size of the heat source was decreased. Expressions are given which define the variation of the hot surface ignition temperatures of these combustibles with the radius and the surface area of the heat source. The expressions are applicable to stagnant or low velocity flow conditions (less than 0.2 in./sec.). In addition, the hot gas ignition temperatures of the combustible vapor-air mixtures were determined with jets of hot air. These ignition temperatures also varied little with fuel-air ratio and increased as the diameter of the heat sources was decreased.

Pelouch, J. J., Jr.↗

Bibliography on aircraft fire hazards and safety. Volume 2: Safety. Part 1: Key numbers 1 to 524

Bibliographic citations are presented to describe and define aircraft safety methods, equipment, and criteria. Some of the subjects discussed are: (1) fire and explosion suppression using whiffle balls, (2) ultraviolet flame detecting sensors, (3) evaluation of flame arrestor materials for aircraft fuel systems, (4) crash fire prevention system for supersonic commercial aircraft, and (5) fire suppression for aerospace vehicles.

Pelouch, J. J., Jr.↗

Unpowered to powered failure rate ratio - A key reliability parameter

It is shown that the initial assumption of the ratio of unpowered to powered failure rates can have a strong influence on the design of a modular system intended for space missions. The analysis is performed for parallel systems and for triple modular redundant systems. Parallel systems are shown to be much more sensitive to the unpowered to powered failure rate ratio than the TMR/Spares systems, however, regardless of which standby redundancy technique is considered, the dependence of the system reliability on this ratio increases as the number of standby spares increases.

Taylor, D. S.↗

Power spectrum analysis of staggered quadriphase-shift-keyed signals

Mathematical analysis of power spectrum of outputs from high-reliability communication system is used to determine system bandwidth. Analysis provides mathematical relationships of signal power spectrum at output of hard limiter for any type of baseband pulse input subjected only to output parameter constraints.

Mcwhorter, F. L.↗

The Space Shuttle - Key considerations

Typical Space Shuttle flight operations, including launch/insertion, on-orbit operations, de-orbit, and ground turnaround, are summarized. The orbiter, main engine, and solid rocket boosters will be reusable. The Shuttle will be able to abort ascent and return the orbiter plus payload to the launch site if necessary. Mission capabilities include a 7-30 day duration, crew of 4-7 (with 1-4 payload specialists), and 14,500-29,500 kg payloads. Payload accommodations, including cabin, crew provisions, pointing and position stability, thermal constraints, electric power, communications, payload deployment and retrieval, contamination control, and kits for extended missions, are considered. The Thermal Protection System, utilizing pyrolized carbon and silica tiles, is described. The Space Shuttle Main Engine design and performance are considered and compared to those of the J-2 engine used on Saturn/Apollo missions.

Malkin, M. S.↗

The high intensity solar cell - Key to low cost photovoltaic power

This paper discusses the problems associated with conventional solar cells at high intensities and presents the design considerations and performance characteristics of the 'high intensity' (HI) solar cell which appears to eliminate the major problems. Test data obtained at greater than 250 AM1 suns gave a peak output power density of 2 W per sq cm at an efficiency exceeding 6% with an unoptimized cell operating at over 100 C. It appears that operation at 1000 AM1 suns at efficiencies greater than 10% is possible. At 1000 AM1 suns and 10% efficiency, the HI cell manufacturing cost is estimated to be $0.25/watt, with multi-megawatt annual production capability already existing within the industrial sector. A high intensity solar system was also analyzed to determine its cost effectiveness and to assess the benefits of further improving HI cell efficiency.

Sater, B. L.↗

Data monitoring and information availability - A key to solar energy utilization

Widespread use of solar energy heating and cooling systems is dependent upon their price competitiveness with other systems in the marketplace. There are indications that the degree of accuracy of existing solar insolation data is such that systems must be oversized by 50 percent. Refinement of the solar insolation data could result in a substantial cost reduction of solar heating and cooling systems making these units more competitive with conventional systems. This paper describes a system, the Sunfall Monitor, that provides this capability. The system monitors and records on tape in computer-compatible format the values of the direct and total solar irradiance. Provisions are also incorporated for evaluation of solar cell, collector and absorber material samples. Concepts and discussions for application of the device in relationship to research/development and the solar energy heating and cooling acts conclude the paper.

Kemp, A. J.↗

Tracking a phase-shift-keyed signal

In detector, phase shifter is used to generate negative phase shift opposing detected phase angle. This produces converted series sideband and component carrier, with residual carrier signal and converted series sideband and component carrier added together to produce tracking signal.

Villarreal, S.↗